Under the terms of the agreement, Britain will remain tied to EU trade rules until at least the end of 2020

Donald Trump - Image credit: Press Association

Donald Trump has warned Theresa May that her Brexit deal could make it difficult for the UK to trade with America after it leaves the EU.

In another blow for the Prime Minister's blueprint, the US president said the draft withdrawal agreement was “a great deal for the EU”.

Speaking outside the White House, President Trump said: "I think we have to take a look at seriously whether or not the UK is allowed to trade because you know right now, if you look at the deal they may not be able to trade with us.

"That wouldn’t be a good thing. I don’t think they meant that, I don’t think the Prime Minister meant that, and hopefully she’ll be able to do something about that.

"But right now as the deal stands they may not be able to trade with the US and I don’t think they want that at all, that would be a very big negative for the deal."

Under the terms of the agreement, Britain will remain tied to EU trade rules until at least the end of 2020, while both sides try to thrash out a free trade deal.

The UK may then extend that period for up to two years, or enter a so-called "backstop" arrangement to avoid a hard border in Ireland by maintaining customs ties with Brussels.

Trump's shock intervention came hours after it was confirmed that MPs would vote on the deal on 11 December.

May faces a major fight to get her plans through the Commons amid growing resistance from MPs on all sides – with more than 90 of her own backbenchers vowing to vote it down.

Responding to Trump’s comments, a Downing Street spokesman said: “The political declaration we have agreed with the EU is very clear we will have an independent trade policy so that the UK can sign trade deals with countries around the world – including with the US.

“We have already been laying the groundwork for an ambitious agreement with the US through our joint working groups, which have met five times so far.

“The US trade representative also issued a call for views from the public on a future UK-US free trade agreement earlier this month.”

Labour MP Tulip Siddiq, a supporter of pro-Remain campaign group Best of Britain, said: “This is a Brexit bombshell and it has blown apart the whole government’s post-Brexit trade strategy.

“Even Donald Trump, not the sharpest tool in the box, knows this deal is a bad deal.

“Theresa May promised a Global Britain, but her Brexit is globally unpopular. Time to ditch this deal and let the people decide through a people’s vote.”